Abstract: An encrypted stream of video information (20) contains first video frames (22) and second video frames which are accessible and not accessible during trick play respectively. From a source stream encrypted that is for decryption with repeatedly changing control words sections of the stream are identified where respective first ones of the frames occur in the stream. Control words for decryption (24) are included in the stream. At least part of the control words are included in the stream at positions selected synchronized to the identified sections.

Abstract: The present invention relates to an authorized domain including a plurality of Authorized Domain Managers (ADMs). The plurality of ADMs contrary to a single ADM solution enables portable ADMs, that do not have to be continuously connected to the AD. The invention provides a solution for keeping the ADMs synchronized. For this purpose, inter alia, each ADM is provided with a map, which comprises an identifier area for containing identifiers corresponding to other devices, and at least one property area for containing properties of the identifiers. The property area is mapped on the identifier area. The properties are arranged to provide information about updates thereof. By obtaining map contents of another ADM, and comparing the contents of the own map with the map contents of the other ADM, it is possible for an ADM to determine whether to perform any updates of the own map.

Abstract: An encrypted stream of video information (20) contains first video frames (22) and second video frames which are accessible and not accessible during trick play respectively. From a source stream encrypted that is for decryption with repeatedly changing control words sections of the stream are identified where respective first ones of the frames occur in the stream. Control words for decryption (24) are included in the stream. At least part of the control words are included in the stream at positions selected synchronized to the identified sections.